FXUS66 KMTR 121742 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 1042 AM PDT Sat Apr 12 2025 ...New AVIATION... .SYNOPSIS... Issued at 230 AM PDT Sat Apr 12 2025 A cooler Saturday is on tap, with a warming trend starting on Sunday and continuing into early next week. Minor HeatRisk returns Sunday and Monday for much of the region, with high temperatures falling a few degrees for midweek placing us closer to normal for this time of year. && .UPDATE... Issued at 901 AM PDT Sat Apr 12 2025 Pretty chilly morning! Temperatures are definitely running colder this morning, with areas seeing anywhere between 5-15 degrees lower than yesterday morning. Therefore, the forecast remains on track with no anticipated changes at this moment. && .SHORT TERM... (Today and tonight) Issued at 230 AM PDT Sat Apr 12 2025 Satellite imagery this morning shows a band of high cloud streaming over the Bay Area and Central Coast. Beneath that, pockets of stratus can be seen in Marin Co, some of the valleys in the East bay, hugging portions of the San Francisco, San Mateo, and Santa Cruz coasts, and finally some sprawling around the Monterey Bay and into the the adjacent valleys. This trend should continue through the morning and generally favor stratus than fog while the winds are up. Should you encounter fog this morning, remember to slow down and leave extra time to reach your destination. Once the stratus mixes out by mid to late morning, look for mostly clear skies. Highs for today peak in the mid 50s to low 60s for much of the coast and low to mid 70s for interior valleys. Tonight, we may see some patches of stratus again, though it may stay more confined to coastal communities along San Mateo County and the Monterey Bay. There is some signal for patchy stratus in the valleys of the North Bay and northern valleys of Monterey County. && .LONG TERM... (Sunday through Friday) Issued at 230 AM PDT Sat Apr 12 2025 No major changes in the long term portion of the forecast. Models and ensembles show weak ridging building into the region by Sunday and then holding through Monday. As a result, we will see a warming trend for this period with high temperatures being about 5 to 15 degrees above average for this time of year. Minor HeatRisk is expected across the region, meaning this level of heat primarily affects those extremely sensitive. A few ways to combat the heat include taking frequent breaks with adequate cooling, staying hydrated, and wearing light colored and loose fitting clothes. As we head into midweek, the pattern changes once again as an upper level low forms off the coast by Tuesday. Ensembles and models generally tend to favor the low forming west of the southern CA, though some models try to creep it towards the southern portion of the Central Coast. This will decrease high temperatures for Tuesday and likely continue the trend into Wednesday and Thursday. Though on Wednesday, cluster analysis shows high pressure building over the eastern Pacific and then nudge its way east towards and into the West Coast towards the latter half of the week. This should spur another warming trend for the weekend. && .AVIATION... (18Z TAFS) Issued at 1040 AM PDT Sat Apr 12 2025 High confidence for VFR conditions to prevail through the remainder of the day with an increase of onshore winds by this afternoon, albeit weaker than yesterday. Wind speeds become light and variable overnight and into early Sunday. Probability of MVFR ceilings will be greatest over the Monterey Bay Terminals early Sunday morning. Vicinity of SFO...VFR. Wind speeds increase this afternoon with gusts up to 25 knots before easing late this evening and into Sunday morning. Onshore winds increase again Sunday afternoon. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...VFR. Onshore winds of 10-12 knots will prevail through this evening before easing and becoming variable into Sunday morning. There is the potential for MVFR ceilings to develop late in the night/early Sunday, however generally about a 50/50 chance of them developing. && .MARINE... (Today through Thursday) Issued at 901 AM PDT Sat Apr 12 2025 A fresh to strong northwesterly breeze persists over the waters with gusts to gale force over the outer waters north of Pigeon Point. Northwesterly swell will build 10 to 12 feet at 10 to 11 seconds with moderate seas expected. Winds begin to diminish and seas subside through Sunday and will persist into midweek. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...Small Craft Advisory until 3 AM PDT Sunday for Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm. Gale Warning until 9 PM PDT this evening for Pt Arena to Pt Reyes 10-60 NM. && $$ SHORT TERM...KR LONG TERM....KR AVIATION...RGass MARINE...RGass Visit us at www.weather.gov/sanfrancisco Follow us on Facebook, X, and YouTube at: www.facebook.com/nwsbayarea x.com/nwsbayarea www.youtube.com/nwsbayarea